keith



Dec. 1o, 1929. w. G. KEnH' ELECTRIC FLASHER 2 Sheets--Sheet Filed OCT.. 16. 1926 Patented Dec. 10, 1.9.29

PATENT OFFICE i WILLIAM e. KEITH, or CHICAGO, ILLINOIS,

ASSIGNOR TO WELSBACB'. TRAFFIC SIGNAL COMPANY, OIF JPHILADELPHIAY, PENNSYLVANIA, A CORPORATION F DELAWARE ELECTRIC FLASHER App1ication filed October 16,

This invention relates to electric flashers and has special reference to electromagneti- 1 cally operated flashers for controlling electric signal devices, electric signs and the like.

More particularly this invention has reference to an electric flasher wherein. a pair of fluid contact-making members are operated by an electromagnet, one of said contact-making .members being adapted to control the electric current for energizing said electr0- magnet, and the other of said contact-making members being adapted to control the electric current for operating the load.

Inasmuch as devices of the character indicated above are continuous in action, it is desirable that such devices be simple in construction, simple in operation, and that they require a minimum amount of electrical current for operation. Moreover, it is particularly desirable to provide a construction which is capable of opening and closing an electric circuit indefinitely and without substantial deterioration or disintegration of the contact-making members,'or of the operating 'mechanism generally.

The present invention, which conforms to the foregoing requisites, comprises a pendulum pivotally connected to a support, which pendulum has a pair of electricswitches, referably tiltable fluid contact-making and reaking members, mounted thereon, and said pendulum being operated by an electromagnet which is controlled by one of said electric switches, While the other of said electric switches is connected to a lamp or otherl suitable load which is controlled thereby.

Fora better understanding of the nature, scope and characteristic features of this invention, reference may now be had to the following description and the accompanying drawings, in which drawings: y

Figure 1 is an elevational view of a signal device inwhich this invention may be ernbodied; I i

Fig. 2 is a sectional view taken on the line 2--2 of Fig. 1 showing the operating mechanism in elevation;

Fig. 3 is a sectional view similar to Fig. 2

taken on the line 3-'3 of Fig. 2;

192e. serial No. 142,013.

Fig. 4 is a plan sectional view taken on the line 4-4 of Fig. 8; and

Fig. 5 is a wiring diagram of the electrical circuit embodied in this invention.

Referring to the drawings, the present invention is shown as embodied in a signal device 10 for illustrative purposes only, since this invention may be employed for operating electric signs, devices for spectacular illumination of all kinds and all devices and apparatus wherein a periodic make and break of a circuit is employed.

The signal device 10 is used as a warning, particularly for motorists, and is placed at the end of a street,'a turn in the road, railway crossings, intersections of streets, etc. This `device comprises a signal head in which is positioned an electric lamp in the upper end thereof in a plane with a lens 11, a support for said signal headand mounted on a container, an electric flasher 12 centrally located in said container and for operating said lamp, and batteries 13 in the lower end of said container for operating said electric flasher and for lighting said electric lamp. In this instance, a plurality of dry cell batteries are employed as the source of electric current because a lamp of low voltage may be used. It is to be understood, however, that any source of electrical supply may be used in this device as various minor replacements may be made to accommodate higher voltages, the representation herein shown being more economical, and therefore, preferable.

The electrical flasher 12 comprises a metal base 14 having an electromagnet 15 mounted thereon, said electromagnet being substantially of the horse-shoe type having a soft iron core around which a coil of wire 16 is wound and insulated therefrom, said core being disposed between two extending arms or brackets 17. A pair of rods 18 are secured to flanges 19 by means of bolts 20, and extend upwardly to be secured to a metal cross-mem ber 21.y and an insulating cap 22 by means of bolts 23.

The flasher 12 is suitably enclosed by a casing 28 fastened to the base 14 at its lower end and fastened to the cross-member 21 at its upper end. This device is perpendicularly susa proper location thereon, said Wire 24 extending to depressed portion 26 of the. sus- Eension rod 27 supported in the container.

y this means of suspension it is possible to regulate or adjust the timing of the mechanism at the factory before shipment therefrom. It will be apparent that the device may now adapt itself for use in various constructions Without further adjustment to the flasher, and moreover, without any adjustment to the construction in which it is installed. Q-

In order to periodically light the lamps in the signal device a pair of tiltable fluid contact-making members 29 and 30 are disposed in clips 29a and 30, respectively, and are mounted on a bracket 31 secured to a pen- -dulum 32. The pendulum consists of an arm 33 extending vertically in the casing and secured at its upper end preferably to a highly flexible phosphor-bronze member 34 which, in turn, is secured to the cross-member 21. A substantially heavy iron member 35 is secured to the lower end of said arm 33 and in a normal inoperative position, rests between the planes coextensive withthe inner surfaces of the brackets 17 and in close proximity to the brackets.

While the pendulum 32'has been specifically described as it is being manufactured for present day use, it is to. be understood that various other constructions are possible to produce a like result. However, the pivotal means being positively secured to its support insures a permanent construction which offers the least possible opportunity of becoming disarranged. Further the use of phosphorbronze in this construction provides a greater durability than any other metal and since the arc of flexure of this phosphor-bronze member is practically nil, the life of this member is practically unlimited.-

The contact-making members 29 and 30 are similar and comprise a container in one end of which two spaced electrodes are hermetically sealed and in which a comp act and coherent body of current-conducting fluid is disposed for bringing said electrodes into electrical conducting relation with one another. The electrodes within the member 29 are connected to lead-in wires 36 and 37 while the electrodes within the member 30 are connected to lead-in wires 38 and 39.

Referring more particularly to Fig. 5, the lead-in wires 37 and 39 are connected to a common terminal 40 while the lead-in Wire 36 is connected to one end of the coil 16, the other end of said coil being connected to the terminal 4L The lead-in wire 38 is connected directly to the terminal 42, the terminals 40, 41 and 42 being mounted on the insulating cap 22. The load or lamp 43 is connected lo terminals 41 and 42 while the batteries 13 are connected to the terminals 40 and 411 It will be noted that the electrodes are positioned in opposite ends of the members 29 and 30 respectively, and that a tilting of the members in the same direction would cause the current-conducting fluid to bridge the electrodes in one member thereby completing the circuit through that member, whereas, the current-conducting fluid in the other of said members would be caused to break the circuit through the latter member.

In accordance with the above mentioned information, it will be assumed that the members 29 and 30 are tilted to a positionl Whereby the current-conducting fluid bridges the electrodes in the member 29. The circuit will be completed from the battery 13 through the terminal 40, the member 29. the coil 13, the terminal 41 and back to the battery. Should the member 29 and 30 be tilted to a position whereby the. current-conducting fluid bridges the elect-redes in the member 30, the circuit would be completed from the batterv 13 through the terminal 40, member 30, terminal 42, `lamp 43, and back tothe battery. Y A tilting of the tubes'in one direction would, therefore, energize the coil, Whereas a tilting of the tubes in an opposite direction would complete a circuit through the lampor other load.

In the operation of the mechanism of the flasher, the pendulum, as hereinbefore stated, rests in its normal inoperative position in close proximity to the electromagnet brackets 17. In this position the currentconducting fluid bridges the electrodes within the tube or member 29 completing an electrical circuit through said tube and, as also hereinbefore explained, the current-conducting fluid in the tube or member 30 occupies a position such that an electrical circuit does not exist therethrough. A passage of electrical current through said tube 29 energizes the coil 16 of the electromagnet 15 and creates an induction therein, thereby drawing the weighted member 35 of the pendulum inwardly until the tubes are tilted to a posi tion whereby 'the current-conducting fluid in the tube 29 flows away from the electrodes and the circuit is broken. The-current-conducting fluid in th'e tube 30 also flows in the same direction as said fluid Within tube 29 and bridges the electrodes in said tube 30 and establishes an electrical circuitt-herethrough to light the lamp.,

As soon as the electrical circuit is broken, through the tube 29, the coil 16 is de-energized and the Weighted member 35 is permitted'to return to its normal position, which action causes the tubes to tilt to their original position wherein the electrical circuit is broken through the tube 30 and completed through the tube 29. The coil is now re-encrgized and the same cycle is repeated, the action of which causes a flashing of the lamp.

is requiredl to vbridge said electrodes and inv an extreme position a full tilt is required before said electrodes are bridged. As the tube SOis held in an extreme position for but an instant, the time of the flash is `extremely short, whereas, when the electrodes occupy a vertical position, said electrodes are bridged before a full tilt of the tube occurs and re` main in a bridged condition for a substantial period after said tube has reversed its direction, and therefore, the Hash period extends substantially longer.

The current-conducting fluid disposed within the contact-making members 29 and 30 is preferably of mercury. Inasmuch as the time period of the flash is unusually limited, it is desirable that the mercurybe highly mobile. In order to provide this characteristic, a small quantity of a solution of hydrocyanic acid, or other compounds of cyanide, may be mixed with the mercury. A quicker acting switch is thus provided permitting a very small angular displacement of the tube member to perform' the circuit making-and-breaking functions required thereby. Summarizing the 'advantages obtained by this highly mobile mass of mercury, a very limited flash period may be obtained and also a very limited period between said flash periods may be obtained.

lVhile it is preferable to embody this invention in the device herein shown and described, various other forms will be apparent to one skilled in the art without departing from the spirit of this invention, and the invention is, therefore, to be limited only by the scope of the appended vclaims and the prior art. v

I claim:

l. In an electric flasher, a tiltable member. a fluid contact-making member mounted thereon .and axially adjustable therewith for controlling an electrical circuit in said electric flasher, and means for actuating sa1d tiltable member, saidcontact-making member adapted to control the length of Hash period in said electric flasher.

2. In an electric Hasher, a tiltable member, a clip member mounted thereon, a Huid contact-making member rotatabl mounted in said clip member for controlling an electrical circuit in said signal flasher, and means for actuating said tiltable member, said contact-makin member adapted to control/the length of ash period in said electric flasher when rotated into various adjusted posit-ions.

3. In an electric flasher, a tiltable member,

of mercury disposed therein whereby when said container is in one position said electrodes will occupy a vertical position therein and the length of Hash will be great and a partial rotation of said container will cause said electrodes to be displaced from a vertical position and said length of Hash will be smaller.

4. In an electric Hasher, a tiltable member, a plurality of Huid contact-making members mounted thereon, and means for actuating said tiltable member, said actuating means being controlled by one of said contact-making members, the remainder of said contactmaking members being mounted on said tiltable member and axially adjustable therewith for controlling the length of Hash periods in said signal Hasher.

5. In an electric Hasher, a tiltable member, a pair of clip members mounted thereon, a pair of Huid contact-making members mounted on said clip member for operatin electrical circuits, and means for actuating said tiltable member, said actuating means being controlled by one of said contact-making' members, the other of said contact-making members being rotatably mounted in said j clip member whereby a rotation thereof controls the length of Hash period in said signal flasher. a

6. In an electric Hasher, a support, a vertically extending member pivotally mounted on said support, a pair of fluid contact-.making members mounted on said vertical member for controlling electrical circuits, and means for actuating said vertical member, said actuating means being controlled by one of said contact-making members, the other of said contact-making members being adjustably mounted on said tiltable member whereby an adjustment thereof controls the length of Hash period in said signal Hasher.

In witness whereof, I have hereunto subscribed my name.

WILLIAM Gr. KEITH. 

